As disclosed in Japanese Patent No. 3498264, a conventional vehicle is equipped with an airbag device for protecting the occupants from load of frontal impacts, and is also sometimes equipped with a curtain airbag device for protecting the occupants from load of side impacts.
The main body of such a curtain airbag device is disposed in a folded manner in the inside of a cabin, along front and rear pillar parts from a roof side rail part of the vehicle body. The main body is inflated by being supplied with gas from an inflator when load of a side impact acts on the vehicle body, and then deploys along the window glasses and pillar inner surfaces.
In this structure, the curtain airbag device on the inside of the cabin is generally provided with a roof trim that covers the roof side rail part and a roof panel, as well as pillar trims that cover the front and rear pillar parts. In this case, a deployment force, generated upon inflation and deployment of the curtain airbag main body, causes the curtain airbag main body to push out the side edge parts of the roof trim and the side edge parts of the pillar trims continuing to the aforementioned side edge parts.
Incidentally, generally a pillar trim is formed of relatively hard resin, while a roof trim is formed of soft resin. However, because of these materials, the following problems might occur upon airbag deployment at an adjacent part between the roof trim and the pillar trim. In other words, since the roof trim is soft, when the roof trim is deformed as the side edge parts thereof are easily pushed out widely downward by the deployment force of the curtain airbag main body being deployed, the pillar trim, although hard, is also deformed at the adjacent part between the pillar trim and the roof trim as the side edge parts of the pillar trim are similarly pushed out widely by the force of the deployment, which might result in damage to the pillar trim.
Japanese Patent No. 3498264 discloses the curtain airbag device in which the curtain airbag main body is folded in the shape of an accordion, the direction of deployment of the airbag is set to a direction of pushing open the roof trim (lid) above the pillar parts (meaning that a gap is formed by moving the roof trim in a separation direction of parting the roof trim away from the roof side rail part) so that the curtain airbag main body is supported while having it partially twisted.
According to Japanese Patent No. 3498264 described above, such a structure is capable of strengthening the force of pushing open the roof trim, the force being generated upon inflation of the curtain airbag main body. This allows the roof trim to be deformed by pushing open a lower end thereof readily. As a result, the pillar parts of the airbag main body can be deployed quickly.
However, this conventional technology disclosed in Japanese Patent No. 3498264 is not designed to prevent damage to the soft pillar trim which is caused by pushing open the hard pillar trim, as it is designed to merely facilitate the deformation of the roof trim by improving the force to push open the roof trim with use of the original softness of the roof trim.